PSSR Written Scheme of Examination Requirements

The Pressure Systems Oversight That Could Get You Fined – or Worse

A surprising number of sites run air compressors that technically fall under the Pressure Systems Safety Regulations 2000 (PSSR) – but have no Written Scheme of Examination (WSE) in place. That includes:

• Garages
• Fitters’ workshops
• Engineering firms
• Small-scale manufacturing units

If that’s you – here’s what to know.

When Does PSSR Apply?

PSSR kicks in when a pressure system exceeds 250 bar litres (bar × internal volume in litres).

Let’s break that down:

• A 100-litre tank at 8 bar = 800 bar litres – well over the threshold.
• Many standard compressors hit this figure, especially those used for spray booths, air tools, or multi-bay servicing.

What Is a Written Scheme of Examination (WSE)?

A WSE is a legally required document that outlines:

• Which parts of the pressure system must be examined
• How often they need checking
• What safety devices are fitted (and how they’re tested)

It must be produced by a competent person and held before the system is used.

Why It Matters

Your safety valve is often the only thing preventing an over-pressurisation event. If it’s:

• Blocked with debris
• Corroded
• Incorrectly set
• Never been tested…

…it may not vent at the right pressure. That’s not just a compliance issue – that’s an explosion risk.

We Can Help

Velocity Safety provides PSSR-compliant inspections and Written Schemes of Examination, working with clients across:

• Engineering
• Civils & construction
• Commercial workshops
• Utilities and manufacturing

Whether you’ve just bought a new compressor, or you’ve got a 5-year-old unit that’s never been checked – now’s the time to act.

👉 Learn more about our PSSR inspections and WSE support